Overload switch



H. WILLMANN.

I OVERLOAD $W|TCH. APPLICATION FILED NOV. 10, I921- Patented Jan. 10, 1922.

2 SHEETS-SHEET l- H. WILLMANN.

OVERLOAD SWITCH.

APPLICATION FILED NOV. I0, 1921.

1 ,403,2 1 7, Patented Jan. 10, 1922.

2 SHEETS-SHEET 2- UNITED STATES PATENT OFFICE.

HANS WILLMANN, OF BERLIN, GERMANY, .ASSIGNOR TO A. K. IHLI, ELEKTROTEKNISK VERKSTED, OF CHRISTIAN IA, NORWAY.

OVERLOAD SWITCH.

Specification of Letters Patent.

Patented Jan. 10, 1922.

Application filed November 10, 1921. Serial No. 514,368.

T 0 aZZ whom it may concern Be it known that I, l-lANs WVILLMANN, a German subject, residing at Liitticherstrasse 50, Berlin N. 65, Germany, have invented certain new and useful Improvements in Overload Switches; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being bad to the accompanying drawings, and to letters or figures of reference marked thereon, which form a part of this specification.

The present invention relates to improvements in maximum overload switches; and its principal objects are: first, to construct the switch and its various component parts in such a manner as to save space, and, second, to avoid the danger of breakage of parts due to careless operation.

Heretofore, maximum overload switches which are designed to carry continuous small overloads and which are also adapted to carry momentary overloads of greater extents, have usually had to be made comparatively large with rel-a ion to switches designed for sustained higher overloads, the reason being that the operating devices must be heavy in order to withstand the stresses put upon them, so that a certain size is accordingly required for each part. Also, it is well known that when the switch is in charge of an inexperienced person, such person is very likely, in spite of his instructions, to turn the handle of the switch in the wrong direction, which may cause breakage of the stop parts, unless the latter be made so strong that they can withstand any stresses imposed upon them under such conditions. This likewise results in the size of the switch parts having to be increased.

According to the invention, the usual operating handle is replaced by one which, in stead of being movable in one direction only to open the switch, can be moved in either direction with equal facility. When the circuit is closed, it can be opened manually by moving the handle of the switch in either direction, irrespective of the automatic circuit-breaking operation; and conversely, when the circuit is open, it canbe closed by moving the switch handle in one direction or the other. To efiect this object, the switch handle preferably consists of a button or the like which may be rotated either to the right or to the left.

An embodiment of the invention is illustrated in the accompanying drawing, in which:

Figures 1 and 2 are front and side views, respectively, showing the parts of the switch in circuit-closing position.

Fig. 3 is a front view showing the position assumed by the parts when the switch is operated manually to open the circuit.

Fig. 3 is a side view of a detail.

Fig. 4 is a side view showing the position of the parts after an automatic operation of the switch to open the circuit.

Fig. 5 is a diagram of the electrical connections.

Fig. 6 is a front view of the invention as applied to a bipolar switch.

Fig. 7 is a diagram of the electrical connections of the bipolar switch.

Referring more particularly to the drawing, the improved overload switch comprises a suitable magnet, the core of which is indi-v cated at c and the winding at c; the magnet also having associated with it an armature A. Current is supplied to the usual contact brushes K through wires which are connected to the device at F and F said brushes K being engageable with the fixed contact K to close the circuit and being provided with suitable spark quenchers 9. These brushes are carried by pivoted switch arms or levers K which are pivoted at their lower ends to a toggle Z, the component members of which are disposed in alinement when the circuit is closed, but swing downward incidental to the circuit breaking operation and in so doing pull the lower ends of the switch levers K inward, thereby moving their upper ends away from each other and, in consequence, disengaging the contact arms or brushes K from contact K and separating the two spark quenchers g. The toggle arms or members are made sulficiently heavy to enable this break-joint action to be effected automatically under certain conditions, as hereinafter explained; but normally said members are held in their alining position by means of a hook it which is pivoted to them at their point of connection and is engaged with the hooked lower end m of a vertical slide m suitably connected to the body or frame F of the device. The hook it has pivoted to it a horizontal link k terminating in a hooked rear end h which is engagable by the lower end of the armature A, the latter being pivotally I the stem of a rotatable operating button a.

connectedto the magnet core a, as indicated in Fig. 8 the height of said opemng and the length of said cross-plece corresponding to the extent of movement which is desired for the break-joint or toggle Z. This button and its cross-piece constitute a manual means or device for operating the switch, the movement of the cross-piece serving to raise and lower the controller slide m. r a

The operation is substantially as follows, assuming that the parts are in the circuitclosing position represented in Figs. 1 and 2, with the arms or brushes K engaging contact K, the slide on and toggle Z raised, the hooks h and m engaged and the crosspiece Z) upright in opening a. If it is desired to open the circuit for any reason, the button a is given a quarter-turn in either direction,'so as to move cross-piece 6 into horizontal position as indicated in Fig. 3. Slide m is no longer supported by said cross-piece and, therefore, drops and exerts its weight against the break-joint or toggle,

which latter acts to rock the switch levers K so as to separate the brushes from contact K and thus break the circuit. The hooks h and m remain engaged during the downward movement of the slide, because the armature A is not attracted at this time and, hence, does not shift link h rearward to release hook it.

In the case of a maximum overload, however, and again assuming that the parts are positioned as in Figs. 1 and 2,-the magnet merelv turning the button in one direction or the other. In the second or automatic both cases, however, the parts may be'returned to normal position by suitably manipulating the button.

The development or modification .illustrated in Figs. 6 and 7 relates to the application of the invention to bi-polar overload switches. Switches of that character, as is well known, generally require double, or nearly double, the space of a single-pole switch; but according to my invention, such defect is overcome by substituting for the contact K a divided contact 76 the two parts or members of which are separated by a layer of insulating material. The conducting wires are connected at F F and F F respectively, and the operation is the same as that previously described.

I claim as my invention 1. In an overload switch, the combination of movable contact-carrying means; a vertically-movable slide for moving the contact-carrying means .into and out of circuitclosing position, said slide and said contact carrying means moving relatively to each other at such time; and a handle rotatable at will in either direction to operate said slide.

2. In an overload switch, the combination of movable contact-carrying means; a vercarrying means moving relatively to each other at such time; and a handle rotatable at will in either direction and provided with a cross-piece cooperative with said slide to shift the same and thereby operate said contact-carrying means.

3. In an overload switch, the combination of movable contact-carrying means; a controller for moving the contact-carrying means into and out of circuit-closing position, said contact-carrying means and said controller moving relatively to each other at such time, said controller having a rectangular opening; and a handle rotatable at will in either direction and provided with a cross-piece arranged in said opening to operate said contact-carrying means.

4. An overload switch, comprising mov able contact-carrying means; means for antomatically moving the contact-carrying means to circuit-breaking position when an overload occurs; and manual means rotatable at will'in either direction to move said means to said position.

5. An overload switch, comprising a pair of movable switch arms; a toggle to which said arms are pivotally connected, said toggle acting to move said arms to circuitbreaking position; electro-magnetic means for automatically effecting the operation of the toggle when an overload occurs; and manual means for effecting the operation of the toggle at will.

6. An overload switch, comprising a pair of movable switch arms; a toggle to which said arms are pivotally connected, said toggle acting to move said arms to circuitbreaking position; electro-magnetic means for automatically effecting the operation of the toggle when an overload occurs; and manual means rotatable at will in either direction to effect the operation of the toggle.

7. An overload switch, comprising a pair of movable switch arms; a toggle to which said arms are pivotally connected, said toggle acting to move said arms to circuitbreaking position; a slide arranged to bear upon said toggle to operate the same; and a manual device associated with said slide to normally hold it in inactive, raised posi tion but operable at will to enable the slide to drop and thereby cause the toggle to move the switch arms to break the circuit.

8. An overload switch, comprising a pair of movable switch arms; a toggle to which said arms are pivotally connected, said toggle acting to move said arms to circuitbreaking position; a slide arranged to bear upon said toggle to operate the same; and a manual device associated with said slide to normally hold it in inactive, raised position but rotatable at will in either direction to release the slide and thereby permit it to drop and actuate the toggle.

9. An overload switch, comprising a pair of movable switch arms; a toggle to which said arms are pivotally connected, said tog gle acting to move said arms to circuitbreaking position; a slide arranged to bear upon said toggle to operate the same, said slide having a rectangular opening; and a handle rotatable at will in either direction and provided with a cross-piece arranged in said opening to normally hold the slide in inactive, raised position, but releasing the slide consequent upon the rotation of the handle.

10. In a bi-pol'ar overload switch, the combination of a contact comprising a pair of separate members with insulation between them; a pair of switch arms disposed at opposite sides of said contact members for cooperation with the same; electromagnetic means for automatically moving the switch arms in opposite directions away from the contact members when an overload occurs; and a device movable manually at will in either direction for moving said switch arms in opposite directions away from said members.

11. In a bi-polar overload switch, the combination of a contact comprising a pair of separate members with insulation between them; a pair of switch arms disposed at opposite sides of the contact members for cooperation with the same; and a handle rotatable at will in either direction to move said switch arms in opposite directions away from said members.

12. In a bi-polar overload switch, the combination of a contact comprising a pair of separate members with insulation be tween them; a pair of switch arms for cooperation with said members; a toggle to which said arms are pivotally connected; and a handle rotatable at will in either direction to operate said toggle and thereby rock said arms out of engagement with said members.

In testimony that I claim the foregoing as my invention, I have signed my name in presence of two subscribing witnesses.

HANS WVILLMANN. lVitnesses Gnonen WILLEY, F. BEATE. 

